Current cancer therapies, including both radiation and chemotherapy, have serious side effects and limited efficacy, and they may display the phenomenon of resistance to the previous treatment method upon recurrence. Thermal therapies, such as hyperthermia and thermal ablation, both in conjunction with known treatment regimes or as stand-alone treatments, have emerged as promising therapeutic methods. Numerous phase II and III human clinical trials have been conducted as co-treatments together with radiation and chemotherapy, and these trials demonstrated an enhancement of therapeutic effect by 13 to 42 percent. Hyperthermia clinical trials at Duke University's Comprehensive Cancer Center were highlighted in the Summer 2005 Newsweek Special Edition on the Future of Medicine.
The state of the art hyperthermia treatment uses a phase array antenna with radio frequencies ranging from 75 to 900 MHz. It is well established in the art that the preferential heating of tumor tissues is achieved primarily due to reduced blood flow out of diseased tissues. This effect has caused cancer cells to be more susceptible to radiation or chemotherapy. However, this small temperature difference (a few degrees) alone is not enough to cause predominate cancer cell apoptosis while keeping healthy cells intact.
What is needed in the art is the ability to selectively heat a small portion of a tumor beyond the level that can be attained by current hyperthermia treatments, subsequently causing an apoptotic or necrotic response, while simultaneously maintaining a safe temperature in the remaining portions of the tumor (to prevent shock syndrome) and the healthy tissues surrounding the tumor as a valuable pathway to treat cancer. Embodiments of the present invention utilize ferromagnetic resonance heating (FMRH) of tumor-delivered super-paramagnetic (SPM) nanoparticles to provide this additional heating with an image guided surgical precision.